1. Field of the Invention
The present invention relates to a method for preventing or treating a brain edema, an intracranial hemorrhage (especially a recurrence of an intracranial hemorrhage and so on) and a cerebral infarction, which comprises administering a pharmaceutically effective amount of a compound which excellently inhibits a vascular permeability enhancer.
2. Description of the Prior Art
Stroke is a condition of a disease caused by a cerebrovascular disease, which includes a brain edema, an intracranial hemorrhage, a cerebral infarction, a transient ischemic attack, a subarachnoid hemorrhage, etc., each causing many kinds of diseases.
A brain edema occuring in an acute phase of a cerebrovascular disease, including that caused by a head injury, is a phenomenon wherein a blood brain barrier is damaged disorder by cerebral ischemia and the volume of the brain increases by an increase of a body fluid component in cerebral tissues, to which drug treatment such as an administration of a high dose of steroid in a short period and an intravenous injection of a hypertonic solution such as mannitol and glycerol have been generally applied.
A cerebral infarction is that necrosis of brain tissues is caused by a cerebrovascular blood flow disease, which is often caused by a cerebral thrombosis and a cerebral embolism.
On the other hand, a large number of nucleic acid derivatives have been synthesized so far and their pharmacological activities have been examined. And it has been reported that adenosine derivatives of some kind have a coronary vasodilation action and are useful as a medicament for treating an ischemic heart disease such as a coronary insufficiency, an angina pectoris and myocardial infarction, and a hyperpiesia (U.S. Pat. No. 3,819,613, U.S. Pat. No. 4,255,565, U.S. Pat. No. 4,225,591, U.S. Pat. No. 4,341,769 and JP-A-58 83698, etc.).
Furthermore, EP-0526866-Al1 (disclosed in Feb. 10, 1993) describes that 5'-deoxy-5'-alkylthioadenosine such as 5'-deoxy-5'-methylthioadenosine (MTA) can be used for treating an ischemia with the results of the experiments using a heart ischemia model of rabbit.
Nowadays, steroids used for treating a brain edema have adverse effects such as bleeding of a digestive tract, abnormality of electrolyte metabolism, abnormality of sugar metabolism and complication of infections, while in an administration of the hypertonic solutions, stop of the administration causes phenomena such as another rise in cerebrospinal pressure, so that recently, they have not been used so often. Besides, a medicinal therapy of a cerebral hemorrhage is just a symptomatic treatment and there is no effective medicament to prevent a relapse of an intracranial hemorrhage. The same is true of a cerebral infarction. Under these circumstances, there is no medicament which is desirable from the viewpoint of effects or adverse effects in preventing or treating a brain edema, an intracranial hemorrhage and a cerebral infarction.
Therefore, development of medicaments which can prevent or treat a brain edema, an intracranial hemorrhage and a cerebral infarction, especially a relapse of them, has been desired.